Rolling mills

ABSTRACT

A multi-stand rolling mill comprises two or more selectively interchangeable rows of rolling stands such that only one row is operatively arranged in the rolling line while the other is being serviced. The spacing of the roller axes in all the stands of one row is substantially uniform but somewhat greater than that in the stands of the other row. To enable the rollers to be re-used a large number of times, new rollers of a first larger nominal diameter are initially used in the last stage at the delivery end of the row of stands with the larger roller axes spacing. Thereafter they are progressively transferred from stage to stage, together with the stand itself, to the first stage at the input end of the row, the rollers being refinished at each transfer. The worn rollers from the first stage are turned down to a second smaller nominal diameter and used successively in the second row of roller stands, whose roller axes spacing is smaller, in the same way as in the first row.

United States Patent 1 Bindernagel 51 Apr. 10, 1973 ROLLING NHLLSPrimary ExaminerMilton S. Mehr 75 Inventor: Ali Bindernagel, 4Dusseldorf, Ger- Blenk zlesenhem many 57] ABSTRACT D ld If, G v [73]Asslgnee' :gz Kocks usse 0 er A multi-stand rolhng mill comprises two ormore y selectively interchangeable rows of rolling stands such ['22] F14 1971 that only one row is operatively arranged-in the rolling linewhile the other is being serviced. The spacing of PP N05 133,970 theroller axes in all the stands of one row is substantially uniform butsomewhat greater than that in the [30] Foreign Application p i i Datastands of the other row. To enable the rollers to be re- 1 used a largenumber of times, new rollers of a first Apr. 16, 1970 Germany ..P 20 18l57.1 larger nominal diameter are initially used in the last stage atthedelivery end of the row of stands with the [52] US. Cl ..72/234, 7 larer roller axes pacing. Thereafter they are progres- [51] Int. Cl. ..B2lb13/08, BZlb 31/08 Sively transferred f Stage to Stage, together with[58] Field of Search ..72/238, 239, 234, the Stand itself, to the firstStage at the input end of 72/226 the row, the rollers being refinishedat each transfer. The worn rollers from the first stage are turned down1 References Cited to a second smaller nominal diameter and usedsuccessively in the second row of roller stands, whose UNlTED STATESPATENTS roller axes spacing is smaller, in the same way as in the1,810,167 6/1931 George ..72/234 X first IOW. 1,833,376 11/1931Sirnmons.... ..72/226 3,355,923 12/1967 Gillet ",72/239 x 4 Clams, 2Drawmg Flgures FATENTFU 3,726,119

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Ali Bindernoqol ROLLING MILLS The invention relates to a multi-standrolling mill having at least two interchangeable rows of rolling standshaving non-adjustable rollers, and to a method of utilizing the rollersseveral times in such a rolling mill by refinishing the worn rollers.

In a previously proposed multi-stand rolling mill, the worn rollerswhich have been made usable again by reconditioning, and whose diametershave consequently been changed, are fitted into still centrally drivableinterchangeable stands having an intermediate drive mechanism adapted tothe changed diameters of the rollers. With appropriate choice of theinterchangeable stands, the refinished rollers can be used several timesin the rolling mill at the same stand location or at different places.In this method, in which the rollers are reused frequently and may beutilized to good advantage, the rollers have to be removed from thestand and fitted into the interchangeable stand each time the rollersare exchanged.

Furthermore, in a row of roller stands having non-adjustable rollers, ithas also been proposed to progressively transfer the rollers from thedelivery end of the rolling line to the input end through the row ofrolling stands, the nominal diameter of the rollers remaining constantor being only slightly changed each time the rollers are refinished. Inthis method, the rollers do not have to be removed from the individualstands, but, after refinishing, which is effected in the stand, they areplaced in the prescribed position in the row together with the entirestand.

Two identical rows of stands are usually provided in order to shortenthe waiting times when the rollers are exchanged, one of which rows islocated in the rolling line, while the other row is being prepared forthe rolling operation, and is exchanged for the row located in therolling line by means of a change-over carriage when the rollers in therolling line have been worn to a specific degree. However, the rollerscannot be used again after a single pass through one of other of therows of stands.

The present invention seeks to combine the ad vantages of the twoabove-mentioned methods and to largely eliminate the disadvantages ofsaid methods.

A multi-stand rolling mill, according to the present invention,comprises at least two interchangeable rows of roller stands havingnon-adjustable rollers, the distances between roller axes in theindividual rows being uniform or differ only slightly from one anotherand the distances between axes from row to row being different. In sucha rolling mill, the rollers in the first instance progress from thedelivery end to the input end through the roll line having the greatestdistances between axes, the worn rollers being refinished with theretention of the nominal or idea] diameter. The ideal diameter ofrollers is reduced after progressing through one row and the rollers arethen progressed through the row having the lesser distances betweenroller axes, the work rollers then being refinished with the retentionof the new ideal diameter.

In accordance with the method of the invention, the rollers may progressthrough the same stage or station in the rolling line several timesowing to the reducing distances between roller axes in the rows ofroller stands and, with the exception of the change to the row havingthe lesser distances between axes, do not have to be removed from theirstand.

The invention is further described, by way of example, with reference tothe accompanying drawings, in which:

FIG. 1 is a diagrammatic illustration of two interchangeable lines ofroller stands, and

FIG. 2 shows the portion of a roller illustrating the individualrefinishing stages.

As shown in FIG. 1 two interchangeable rows 10 and 12 of rolling standsare provided. The row 10 is located in the rolling line, the rollingdirection being indicated in the drawing by the arrow 14. The row 12 hasbeen removed from the rolling line for servicing by means of a standexchange carriage before installing the row 10 and is located at anassembly place where the worn rollers are refinished and the stands aretransposed within the row. When the rollers in the stands of the row 10become worn and require attention, the row 10 of stands is replaced bythe row 12, and vice versa.

Each of the diagrammatically illustrated rows 10 and 12 of stands, whichare part of a wire rolling mill for example, comprises eight stands 16or 16' which are arranged in positions 1 to 8 in the row 10 and inpositions 1 to 8' in the row 12. Each of the stands 16 and 16 containsthree disc-like rollers which form the pass, one of which rollers isillustrated diagrammatically in a simplified form in FIG. 2.

The distances between the roller axes in the stands of the two rows arenot adjustable and are uniform within each row, but differ from oneanother from one row to the other. In the present example, the distancebetween the roller axes in the stands 16 of the row 10 is greater thanin the stands 16' of the row 12. Rollers, as illus trated in FIG. 2,having an ideal diameter D having to be fitted into the stands 16 of therow 10, and rollers having an ideal diameter D having to be fitted intothe stands 16' of the row 12. The peripheral speeds of the rollers ofdifferent diameters in the different rows can be equalized byappropriately modified gear ratios.

The refinishing stages 1 to 8 and 1' to 8 shown on the disc-like rollerin FIG. 2 are associated with the stand positions indicated by the samenumerals in the rows 10 and 12.

The fresh rollers are first of all installed in the stand which islocated at the delivery end of the row 10 and which is indicated byposition 1 in FIG. 1. The rollers,

which become worn with respect to their ideal diameter D together withtheir respective stands, are then progressively transferred through allthe positions 2 to 8 in the row 10 without removing the rollers fromtheir stands. At each transfer the rollers are refinished withoutremoving them from their respective stands. The rollers subjected towear at position 8 of the row 10 are taken out of use while they arere-machined to the ideal diameter D and are then fitted into a stand inthe row 12 having the lesser distance between roller axes. This stand isfirst of all disposed in position 1 at the delivery end of the row 12and is progressively transferred through the other stages 2' to 8' andthe rollers are subjected to their respective refinishing operations.

The rollers which have passed through the second row 12 are scrapped ormay pass through a third row (not illustrated in the drawings) with afurther reduced ideal diameter.

In the foregoing specification I have set out certain preferredembodiments and practices of my invention, however it will be understoodthat this invention may be otherwise embodied within the scope of thefollowing claims.

I claim:

1. In a multi-stand rolling mill, a plurality of roller stands havingrollers journalled therein for rotation about non-adjustable rolleraxes, said roller stands being arranged in at least two interchangeablerows of successive roller stands, each row on a base, a selected one ofsaid rows being movable to an operative position in a rolling line, thedistances between said roller axes in the stands in any individual oneof said rows being substantially uniform from one stand to another, andthe distances between said roller axes being different from one row toanother.

2. In the operation of a multi-stand rolling mill having a plurality ofroller stands each having rollers journalled for rotation about rolleraxes, said roller stands being arranged in at least two interchangeablerows of successive roller stands on a base, of which only a selected onerow is in operative position in a rolling line at any one time, a methodof re-utilizing said rollers comprising the steps of using rollers of afirst nominal diameter in the first instance'in a roller stand at afinal rolling stage at the delivery end of a first of said rows,transferring the rollers to a preceding rolling stage and re-finishingthe rollers, using the rollers at said preceding stage, removing wornrollers from the initial stage at the input end of said first row,remachining the worn rollers to a second nominal diameter smaller thanthe first nominal diameter, using the rollers of the second nominaldiameter in the first instance in a roller stand at a final rollingstage at the delivery end of a second of said rows, the spacing betweenthe axes of the rollers in stands of the second row being smaller thanthat in stands of the first row, transferring the rollers of the secondnominal diameter to a preceding rolling stage in the second row andrefinishing such rollers, and using the last mentioned rollers at saidpreceding stage.

3. A method according to claim 2 in which the spacing between the rolleraxes is substantially uniform in all the stands of the first row and issubstantially uniform in all the stands of the second row.

4. A method according to claim 2 in which the first mentioned rollerstand is transferred with said rollers therein to said preceding stageand said refinishing is performed without removing said rollers fromsaid stand.

1. In a multi-stand rolling mill, a plurality of roller stands havingrollers journalled therein for rotation about nonadjustable roller axes,said roller stands being arranged in at least two interchangeable rowsof successive roller stands, each row on a base, a selected one of saidrows being movable to an operative position in a rolling line, thedistances between said roller axes in the stands in any individual oneof said rows being substantially uniform from one stand to another, andthe distances between said roller axes being different from one row toanother.
 2. In the operation of a multi-stand rolling mill having aplurality of roller stands each having rollers journalled for rotationabout roller axes, said roller stands being arranged in at least twointerchangeable rows of successive roller stands on a base, of whichonly a selected one row is in operative position in a rolling line atany one time, a method of re-utilizing said rollers comprising the stepsof using rollers of a first nominal diameter in the first instance in aroller stand at a final rolling stage at the delivery end of a first ofsaid rows, transferring the rollers to a preceding rolling stage andre-finishing the rollers, using the rollers at said preceding stage,removing worn rollers from the initial stage at the input end of saidfirst row, remachining the worn rollers to a second nominal diametersmaller than the first nominal diameter, using the rollers of the secondnominal diameter in the first instance in a roller stand at a finalrolling stage at the delivery end of a second of said rows, the spacingbetween the axes of the rollers in stands of the second row beingsmaller than that in stands of the first row, transferring the rollersof the second nominal diameter to a preceding rolling stage in thesecond row and refinishing such rollers, and using the last mentionedrollers at said preceding stage.
 3. A method according to claim 2 inwhich the spacing between the roller axes is substantially uniform inall the stands of the first row and is substantially uniform in all thestands of the second row.
 4. A method according to claim 2 in which thefirst mentioned roller stand is transferred with said rollers therein tosaid preceding stage and said refinishing is performed without removingsaid rollers from said stand.